Trachea
(derivation uncertain). A small genus of Night-moths (Noctuae), of which only one species, T. piniperda, or the Pine Beauty Moth, is found in Britain. The size, form, and markings of the moth are shown. The front wings are brick-red, or reddish-brown, mixed with grey and pale orange; there are darker oblique cross-lines, and whitish spots towards the middle of each wing, the centre of the larger spot being filled up with orange-grey. The moths fly in the early spring. The larvae are slender; when full-grown, they are yellowish-green, with a white line down the middle of the back, and a double line (white above, and orange beneath) along each side above the legs. The young larvae are of a uniform green colour. They feed on the leaves of Fir-trees during summer, and, when full-fed, spin slight cocoons in crevices of the bark, or under the soil, and in them become brown pupae. Where these Moths are conspicuously hurtful to Conifers, their numbers may be reduced by shaking them off the branches, and preventing them from ascending the trunk by putting a ring of tar around it. The pupae also should be sought for in the crevices of the bark, and by turning up the soil around the trunks to a depth of three or four inches. This insect is, however, seldom so abundant as to do much harm in any part of Britain.